Final DNA Structure and Replication

Multiple Choice

Which of the following best describes the structure of DNA as shown in the images?

• DNA is a single-stranded molecule found only in some cells.

• DNA is a double-stranded molecule packed within chromosomes in every cell.

• DNA is made up of proteins and lipids.

• DNA is a triple-stranded molecule found in the cytoplasm.

Multiple Choice

What are the three main components of a nucleotide in DNA?

• Phosphate group, pentose sugar, nitrogenous base

• Amino acid, phosphate group, ribose sugar

• Phosphate group, ribose sugar, fatty acid

• Nitrogenous base, lipid, glucose

Multiple Choice

Which of the following are pyrimidines found in DNA?

• Adenine and Guanine

• Thymine and Cytosine

• Adenine and Thymine

• Guanine and Cytosine

Open Ended

Explain the difference between purines and pyrimidines in the structure of DNA.

Open Ended

Describe the types of bonds that hold the sides of the DNA ladder together and the bonds that hold the bases together.

Multiple Choice

Which of the following base pairs are correctly matched in DNA?

• Adenine with Thymine, Guanine with Cytosine

• Adenine with Cytosine, Guanine with Thymine

• Adenine with Guanine, Cytosine with Thymine

• Adenine with Thymine, Guanine with Thymine

Open Ended

Explain how Chargaff’s rules help us understand the structure of DNA.

Multiple Choice

According to Chargaff’s rules, the number of guanine nucleotides must equal the number of which other nucleotide in DNA?

• cytosine nucleotides

• adenine nucleotides

• thymine nucleotides

• thymine plus adenine nucleotides

Multiple Select

Which of the following statements about DNA base pairing are correct?

• A pairs with T

• G pairs with C

• A pairs with G

• C pairs with T

Open Ended

Explain how chromatin is formed and its significance in chromosome structure.

Multiple Select

Which of the following are components of nucleosomes?

• DNA

• Histones

• RNA

• Lipids

Multiple Choice

What is the function of replication forks during DNA replication?

• They are the sites where separation and replication occur

• They are enzymes that synthesize DNA

• They are proteins that bind to DNA

• They are the ends of chromosomes

Open Ended

Explain the role of the enzyme helicase during DNA replication.

Multiple Select

Which of the following are involved in the formation of a new DNA strand during replication?

• DNA polymerase

• Helicase

• Nitrogen bases

• Ribosomes

Multiple Choice

order of replication

• 3, 2, 1, 4
• 2, 1, 4, 3
• 2, 3, 1, 4
• 3, 4, 1, 2

Open Ended

Describe the semi-conservative model of DNA replication and its significance.

Multiple Choice

Arrange the following steps of DNA replication in the correct order: (1) DNA polymerase adds nucleotides, (2) Helicase unwinds DNA, (3) DNA polymerase proofreads the new strand.

• 2, 1, 3

• 1, 2, 3

• 2, 3, 1

• 3, 2, 1

Multiple Choice

Which letter in the picture below depicts the lagging strand in DNA replication?

• Letter A since it is copied from 5' to 3'

• Letter A since it is copied from 3' to 5'

• Letter B since it is copied from 3' to 5

• Letter B since it is copied from 5' to 3'

Open Ended

What is one question you still have about DNA structure, replication, or how DNA affects traits?